This question is asking you to find how much titanium there is in FeTiO3.
First, let's add up all of the elements to find the total mass of the compound.
We know that there is 1 iron, 1 titanium, and 3 oxygen. We will reference the periodic table, and use the element's atomic weight.
Fe x 1: (55.85g x 1) = 55.85g
Ti x 1: (47.87g x 1) = 47.87g
O x 3: (16.00g x 3) = 48.00g
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+ 151.72g
Now to find the percentage of titanium in the compound, we are going to divide the atomic weight of titanium by the total weight of the compound, and multiply by 100.
(weight of Ti) / (total weight of FeTiO3) x 100 = percent of Ti%
47.87g / 151.72 x 100 = 31.55%
